This is a conference grant proposal for support of the ASM sponsored meeting "A Cell Biology Approach to Microbial Pathogenesis," to be held April 25-28, 1999, in Portland, Oregon. In the past, the emphasis of microbial pathogeneses research understandably was weighted towards the identification and detailed characterization of microbial virulence factors and towards understanding the regulation of virulence gene expression. In recent years, a significant number of microbial pathogenesis researchers have developed an interest in understanding how pathogens interact with various host cell components and usurp host cell machinery for their own purposes. This new research emphasis in probing microbial lifestyles at a variety of subcellular levels are made feasible by technical advances in the field of cellular biology and cellular biochemistry. Recent discoveries from the virology, parasitology and bacteriology fields indicate that these apparently disparate microbes may use common mechanisms to deal with their host cells. Yet, most microbial pathogenesis meetings are organism-specific or tend to cover issues limited to bacteria, parasites or viruses. This meeting will present the latest findings in various areas of cell function and present examples from microbial systems that interact with these subcellular components. Microbes to be covered will include viruses, bacteria and protozoans, and will highlight those that have been investigated using cellular approaches. This meeting will provide investigators in the microbial pathogenesis and the cell biology and cellular biochemistry fields an opportunity to interact with each other. Such a forum should stimulate exchanges of ideas, precious reagents and establishment of collaborations, as well as provide an opportunity for students to evaluate an array biological systems for potential future research training.